JP3185930B2 - Integrated tunable optical filter - Google Patents

Integrated tunable optical filter

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Publication number
JP3185930B2
JP3185930B2 JP50761594A JP50761594A JP3185930B2 JP 3185930 B2 JP3185930 B2 JP 3185930B2 JP 50761594 A JP50761594 A JP 50761594A JP 50761594 A JP50761594 A JP 50761594A JP 3185930 B2 JP3185930 B2 JP 3185930B2
Authority
JP
Japan
Prior art keywords
optical filter
waveguide
filter element
spectrum response
section
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
JP50761594A
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Japanese (ja)
Other versions
JPH07501628A (en
Inventor
ウィレムス,ジャン
バエッツ,ロイル
Original Assignee
アンテルユニヴェルシテール・ミクロ・エレクトロニカ・サントリュム・ヴェー・ゼット・ドゥブルヴェ
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Publication of JPH07501628A publication Critical patent/JPH07501628A/en
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Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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Classifications

    • GPHYSICS
    • G02OPTICS
    • G02FOPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/29Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the position or the direction of light beams, i.e. deflection
    • G02F1/31Digital deflection, i.e. optical switching
    • G02F1/313Digital deflection, i.e. optical switching in an optical waveguide structure
    • G02F1/3132Digital deflection, i.e. optical switching in an optical waveguide structure of directional coupler type
    • G02F1/3133Digital deflection, i.e. optical switching in an optical waveguide structure of directional coupler type the optical waveguides being made of semiconducting materials
    • GPHYSICS
    • G02OPTICS
    • G02FOPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F2201/00Constructional arrangements not provided for in groups G02F1/00 - G02F7/00
    • G02F2201/30Constructional arrangements not provided for in groups G02F1/00 - G02F7/00 grating
    • G02F2201/307Reflective grating, i.e. Bragg grating
    • GPHYSICS
    • G02OPTICS
    • G02FOPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F2203/00Function characteristic
    • G02F2203/05Function characteristic wavelength dependent
    • G02F2203/055Function characteristic wavelength dependent wavelength filtering
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01SDEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00Semiconductor lasers
    • H01S5/10Construction or shape of the optical resonator, e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region
    • H01S5/1028Coupling to elements in the cavity, e.g. coupling to waveguides adjacent the active region, e.g. forward coupled [DFC] structures
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01SDEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00Semiconductor lasers
    • H01S5/10Construction or shape of the optical resonator, e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region
    • H01S5/1028Coupling to elements in the cavity, e.g. coupling to waveguides adjacent the active region, e.g. forward coupled [DFC] structures
    • H01S5/1032Coupling to elements comprising an optical axis that is not aligned with the optical axis of the active region
    • H01S5/1035Forward coupled structures [DFC]
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01SDEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00Semiconductor lasers
    • H01S5/10Construction or shape of the optical resonator, e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region
    • H01S5/12Construction or shape of the optical resonator, e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region the resonator having a periodic structure, e.g. in distributed feedback [DFB] lasers
    • H01S5/1206Construction or shape of the optical resonator, e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region the resonator having a periodic structure, e.g. in distributed feedback [DFB] lasers having a non constant or multiplicity of periods
    • H01S5/1209Sampled grating

Abstract

An integrated tunable optical filter comprising a substrate made of a semiconducting material. The substrate includes first and second sections. The first section forms a tunable transmission filter, based on a codirectional coupler having a low selectivity. The second section forms a reflection filter with a reflection spectrum containing a number of peaks. A first injector, designed for current injection into said first section, is provided. Thus, the filter response of the first section is shifted in wavelength over a large wavelength range. There is also a second injector, designed for current injection into the second section. As a result, the reflective spectrum of the second section is slightly shifted in wavelength, in such a way that one reflection peak of the reflection spectrum corresponds to the coupling wavelength of the first section. Consequently, the total filter response has a very narrow bandwidth and wide tunability.

Description

【発明の詳細な説明】 技術背景 本発明は広範な同調可能波長範囲を有する、特に、改
良型WDM(波長分割多重伝送)用とか種々の光部品の分
光試験に使用される、集積可変波長光フィルタに関す
る。
The present invention relates to an integrated tunable wavelength light having a wide tunable wavelength range, particularly for use in improved WDM (Wavelength Division Multiplexing Transmission) and for spectroscopic testing of various optical components. Regarding filters.

広範に同調光波長を可変とする光フィルタは光通信シ
ステムにおいては重要な構成部分である。この種のフィ
ルタにより達成すべき2つの課題がある。その1つは同
調可能波長範囲を広範なものにすることと、もう1つは
スペクトル選択性を高いものにすることである。しかし
ながら、従来知られているプレーナ集積光構造部品では
上記課題の一方のみしか達成し得なかった。
An optical filter capable of widely varying the tuning light wavelength is an important component in an optical communication system. There are two issues to be achieved by this type of filter. One is to increase the tunable wavelength range and the other is to increase the spectral selectivity. However, only one of the above-mentioned problems can be achieved with a conventionally known planar integrated optical structure component.

従来、同方向結合器として公知のフィルタ構造体は、
“広範に同調可能なInGaAsP/InP(インジュウムガリウ
ムヒ素リン/インジュウムリン)埋め込みリブ状導波路
垂直結合フィルタ”(R.C.Alferness、L.L.Buhl、U.Kor
en、B.I.Miller、M.G.Young、T.L.Koch、G.A.Burrus、
G.aybon)、Apply.phys.Lett.第60巻第8号、1992年2
月24日に記述されている。この公知の構造は相異なった
実効屈折率を有する2つの非対称の導波路部により構成
される。上導波路部に導入された光信号が下導波路部に
射出され、上導波路部に向けて選択的に反射される。上
記導波路部のパラメータを適当に選択すれば、この種の
構造体は波長選択性フィルタとして作用させることがで
きる。
Conventionally, a filter structure known as a codirectional coupler is:
"Widely tunable InGaAsP / InP (indium gallium arsenide phosphorus / indium phosphorus) embedded rib waveguide vertical coupling filter" (RCAlferness, LLBuhl, U.Kor
en, BIMiller, MGYoung, TLKoch, GABurrus,
G.aybon), Apply.phys.Lett. Vol. 60, No. 8, February 1992
Written on March 24. This known structure consists of two asymmetric waveguide sections having different effective refractive indices. The optical signal introduced into the upper waveguide is emitted to the lower waveguide and is selectively reflected toward the upper waveguide. By properly selecting the parameters of the waveguide section, this type of structure can function as a wavelength-selective filter.

この公知の構造体の利点は実際同調可能波長範囲が広
範ではあるが、この反面、構造体の全長を長くしないこ
とには高選択性を得ることが困難でる。
The advantage of this known structure is that the tunable wavelength range is wide in practice, but on the other hand, it is difficult to achieve high selectivity without increasing the overall length of the structure.

一方、高選択制を有する半導体光フィルタが知られて
いる。この公知の構造体は上部にグレーティングを成長
させた導波路部を利用するものであり、該グレーティン
グ部は周期的に欠損させられたものである。この種の構
造は既に波長可変レーザに使用されている(V.Jayarama
n、D.A.Cohen、L.A.Coldren、“1つのグレーティング
例を用いた半導体レーザにおける同調範囲の拡大化の実
証例”、Appl.Phys.Lett.第60巻第19号、1992年5月11
日)。しかしながら、この種の構造体をフィルタ構造体
に使用されたものはこれまで存在しない。
On the other hand, a semiconductor optical filter having a high selectivity is known. This known structure utilizes a waveguide portion on which a grating is grown, and the grating portion is periodically deleted. This type of structure has already been used in tunable lasers (V. Jayarama
n, DACohen, LAColdren, "A demonstration of extending the tuning range in a semiconductor laser using one grating example", Appl. Phys. Lett., Vol. 60, No. 19, May 11, 1992
Day). However, no such structure has been used in a filter structure.

この従来の構造体は櫛歯状反射スペクトルを提供す
る。その各パラメータは各ピーク間の間隔、櫛歯状スペ
クトルのエンベロープのスペクトル帯域幅、ピーク値及
び反射ピークの帯域幅等である。該構造体の選択性に影
響を及ぼす、反射ピーク帯域幅が最も重要なパラメータ
である。このパラメータは、非常に残念なことに、該構
造体の同調可能波長範囲を制限することとなっている。
This conventional structure provides a comb-like reflection spectrum. The parameters are the interval between the peaks, the spectral bandwidth of the envelope of the comb-like spectrum, the peak value, the bandwidth of the reflection peak, and the like. The reflection peak bandwidth is the most important parameter affecting the selectivity of the structure. This parameter very unfortunately limits the tunable wavelength range of the structure.

本発明の要約 本発明の目的は広範な同調可能な波長範囲を有すると
同時に高スペクトル選択性を有する、小型集積部分を構
成する光フィルタを提供することにある。
SUMMARY OF THE INVENTION It is an object of the present invention to provide an optical filter which has a wide tunable wavelength range and at the same time has a high spectral selectivity and which constitutes a small integrated part.

上記目的を達成するため、本発明は一方の面に共通電
極を有する半導体基板により形成した集積光フィルタを
提供するものであり、該半導体基板に第1導波路部が設
けられ、該導波路部の上方にグレーティングが成長させ
られている。上記グレーティングは大きい周期を有する
第1構造部と、周期的に欠損した小さい周期を有する第
2構造部とを有する。上記半導体基板の第1部分におい
て、上記グレーティングの第1構造部の頂部で該第1構
造部から離間した位置に同方向結合器を形成する第2導
波路部が設けられる。上記第2導波路部の頂部は第1電
極が取り付けられた半導体部分で被覆される。上記半導
体基板におけるグレーティングの第2構造部の頂部に第
2電極が取り付けられる。上記半導体基板の第1部分に
おける両導波路部の屈折率は上記第1電極から注入され
る電流によって制御される。上記第2部分における導波
路部の屈折率は第2電極から注入される電流によって制
御される。
In order to achieve the above object, the present invention provides an integrated optical filter formed by a semiconductor substrate having a common electrode on one surface, wherein the semiconductor substrate is provided with a first waveguide section, A grating is grown above the. The grating has a first structure having a large period and a second structure having a small period that is periodically lost. In a first portion of the semiconductor substrate, a second waveguide portion is provided at a top of the first structure portion of the grating and at a position away from the first structure portion to form a codirectional coupler. The top of the second waveguide is covered with a semiconductor portion to which the first electrode is attached. A second electrode is attached to the top of the second structure of the grating in the semiconductor substrate. The refractive indices of both waveguide portions in the first portion of the semiconductor substrate are controlled by a current injected from the first electrode. The refractive index of the waveguide in the second portion is controlled by a current injected from the second electrode.

図面の簡単な説明 本発明を以下の図面を参照して詳細に説明される。BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be described in detail with reference to the following drawings.

第1図は本発明の機器の概略断面図である。 FIG. 1 is a schematic sectional view of the device of the present invention.

第2図〜第6図はそれぞれ第1図のフィルタ機器の動
作を説明する代表的な動作曲線である。
FIG. 2 to FIG. 6 are representative operating curves illustrating the operation of the filter device of FIG.

発明の詳細な説明 第1図は本発明の光フィルタの構造を示す。この集積
フィルタ機器は、半導体材料、例えばInP(インジュウ
ムリン)から成る半導体基板により構成され、該半導体
基板1は第1部分2と第2部分3から構成される。上記
半導体基板1に半導体材料、例えばInGaAsP(インジュ
ウムガリュウムヒ素リン)により複数の層が形成され、
上方部にグレーティング40が設けられた下導波路部4が
形成される。上記グレーティング40は2つの相異なった
形状寸法の構造部を形成し、すなわち、上記第1部分2
に長い繰り返し周期を有する第1リブ状構造部41と上記
第2部分3に周期的に欠損した鋸歯状又はストライプ状
構造部42とを形成している。上述の鋸歯状構造部42は短
い繰り返し周期をもってストライプ状領域43と非ストラ
イプ状領域44とを交番するように形成されている。上記
リブ状構造部41の周期は代表的に10〜50μmの範囲内の
大きさとされる。上記鋸歯状構造部42の周期は代表的に
1μm以下の大きさとされる。
FIG. 1 shows the structure of an optical filter according to the present invention. This integrated filter device is constituted by a semiconductor substrate made of a semiconductor material, for example, InP (indium phosphide), and the semiconductor substrate 1 is constituted by a first part 2 and a second part 3. A plurality of layers are formed of a semiconductor material, for example, InGaAsP (indium gallium arsenide phosphorus) on the semiconductor substrate 1,
The lower waveguide part 4 provided with the grating 40 in the upper part is formed. The grating 40 forms two differently shaped structures, namely the first part 2.
A first rib-shaped structure portion 41 having a long repetition period and a saw-tooth or stripe-shaped structure portion 42 which is periodically missing in the second portion 3 are formed. The above-mentioned saw-tooth structure portion 42 is formed so as to alternate between the stripe region 43 and the non-stripe region 44 with a short repetition period. The period of the rib-shaped structure portion 41 is typically set to a size in the range of 10 to 50 μm. The period of the saw-tooth structure 42 is typically 1 μm or less.

第1リブ状構造部41の頂部で該第1リブ状構造部41か
ら離間して上導波路部5が設けられ、該上導波路部5は
半導体基板1の第1部分2に対する同方向結合部を形成
する。上記半導体基板の第1部分2の頂部に第1電極6
が設けられ、該第1電極6を介して注入電流が上記第1
部分2に注入可能とされる。また、第2部分3の頂部に
第2電極7が設けられ、該第2電極7を介して注入電流
が上記第2部分3に注入可能とされる。上記半導体基板
1の下面に共通背後電極8が設けられる。
An upper waveguide section 5 is provided at the top of the first rib-shaped structure section 41 and spaced from the first rib-shaped structure section 41, and the upper waveguide section 5 is coupled in the same direction to the first portion 2 of the semiconductor substrate 1. Form a part. A first electrode 6 is provided on top of the first portion 2 of the semiconductor substrate.
Is provided, and the injection current flows through the first electrode 6 to the first electrode.
Injection into part 2 is enabled. In addition, a second electrode 7 is provided on the top of the second portion 3, and an injection current can be injected into the second portion 3 via the second electrode 7. A common back electrode 8 is provided on the lower surface of the semiconductor substrate 1.

本発明の光フィルタは次の作用を行う。光信号が上導
波路部5を通過させられると、ある波長λで100%の光
パワーが下導波路部4を横切って結合される。第1部分
2における同方向結合部におけるスペクトル帯域幅は下
記の関係式にしたがって該第1部分2の長さLcodir、リ
ブ状構造部41の周期及び上記2つの導波路部5、4の実
効屈折率na、nbによって決定される。
The optical filter of the present invention performs the following operations. When an optical signal is passed through the upper waveguide section 5, 100% optical power at a certain wavelength λ is coupled across the lower waveguide section 4. The spectral bandwidth of the first portion 2 in the same direction coupling portion is determined by the following relational expression: the length L codir of the first portion 2, the period of the rib-like structure portion 41, and the effective width of the two waveguide portions 5 and 4. The refractive index is determined by n a and n b .

上記電極6、8間にある電圧を印加して注入される電
流に基づき屈折率na、nbを変化させることにより上記結
合波長は変化させられる。第2図は同方向結合部のある
濾過応答Aを示し、第3図は電流注入により波長が偏移
された場合の同方向結合部のある濾過応答A′を示す。
上記第1部分2における濾過応答は低選択性を有するこ
とに注意しなければならない。
The coupling wavelength is changed by changing the refractive indices n a and n b based on a current injected by applying a voltage between the electrodes 6 and 8. FIG. 2 shows a filtered response A with a co-directional coupling, and FIG. 3 shows a filtered response A 'with a co-directional coupling when the wavelength is shifted by current injection.
It has to be noted that the filtration response in the first part 2 has a low selectivity.

下導波路部4に結合された光信号は周期的に欠損した
鋸歯状構造部42に入る。該欠損した鋸歯状構造部42の反
射スペクトルは、第4図中、第1部分2の濾過応答と一
緒に、Bを付して示されるように鋸歯状のものとされ
る。この鋸歯状スペクトルの各反射ピークは高選択性を
有する。選択性は主に欠損した第2構造部42の周期及び
該構造部42の結合の強さによって決定される。
The optical signal coupled to the lower waveguide section 4 periodically enters the missing saw-tooth structure 42. The reflection spectrum of the missing saw-tooth structure 42, together with the filtration response of the first part 2 in FIG. Each reflection peak of this sawtooth spectrum has high selectivity. The selectivity is mainly determined by the period of the missing second structure 42 and the strength of the connection of the structure 42.

櫛歯状スペクトルBの各反射ピークは電極7、8間に
電圧が印加された後、該第2部分3への注入電流によっ
て僅かに変化させることができる。このようにして、櫛
歯状スペクトルは第5図中B′をもって示すように波長
が幾らか変位させられる。このようにして、反射ピーク
の1つの波長を第1部分2の中心結合波長に正確に対応
させることができる。
After a voltage is applied between the electrodes 7 and 8, each reflection peak of the comb-shaped spectrum B can be slightly changed by a current injected into the second portion 3. In this way, the wavelength of the comb tooth spectrum is displaced somewhat, as indicated by B 'in FIG. In this way, one wavelength of the reflection peak can correspond exactly to the central coupling wavelength of the first part 2.

濾過応答Cが第6図に示すように非常に狭い帯域を有
することとなり、その応答結果が上導波路部5に表れ、
該導波路部5の出力に反映される。
The filtering response C has a very narrow band as shown in FIG. 6, and the response result appears in the upper waveguide section 5,
This is reflected on the output of the waveguide section 5.

上記2つの部分2及び3の種々のパラメータは全体的
に互いに独立的に選択不可能であるが、少なくとも次の
条件を満足しなければならない。この条件は同方向結合
部のスペクトル帯域幅と第2部分3の櫛歯状スペクトル
における各ピーク間における間隔との関係を確立する。
この帯域幅は各ピーク間の間隔よりも小さくしなければ
ならない: ここで、Δλ3dBは同方向結合部のスペクトル帯域幅
である: ここで、 λ ;波長 Δ ;第1部分におけるリブ状構造部の周期 Lcodir;第1部分の長さ na、nb;第1部分における2つの導波路部の実効屈折率 L1 ;第2部分における鋸歯状グレーティング部の1
周期の長さ L2 ;第2部分における非ストリップ状グレーティン
グ部の1周期の長さ n ;第2部分における導波路部の実効屈折率 さらに、また、上記各パラメータの選定は上記グレー
ティング構造部にわたって要求される特性によって制限
される。2つの重要な特性は同調範囲の大きさと選択性
である。同調範囲は第1及び第2部分によって決定さ
れ、2つの変数、すなわち同方向結合部の同調範囲Δλ
及び第2部分3における櫛歯状スペクトルのエンベロ
ープのスペクトル帯域幅Δλの最大値以下の大きさと
される。
The various parameters of the two parts 2 and 3 cannot be selected independently of each other as a whole, but at least the following conditions must be fulfilled: This condition establishes the relationship between the spectral bandwidth of the co-directional coupling and the spacing between each peak in the comb spectrum of the second part 3.
This bandwidth must be less than the spacing between each peak: Where Δλ 3 dB is the spectral bandwidth of the co-directional coupling: Here, λ; wavelength Δ; period of the rib-shaped structure portion in the first portion L codir ; length of the first portion n a , n b ; effective refractive index of the two waveguide portions in the first portion L 1 ; One of the sawtooth grating portions in the two portions
The length of the period L 2 ; the length of one period of the non-strip-like grating portion in the second portion n; the effective refractive index of the waveguide portion in the second portion Further, the above parameters are selected over the grating structure portion. Limited by required characteristics. Two important characteristics are the tuning range size and selectivity. The tuning range is determined by the first and second parts and is controlled by two variables, the tuning range Δλ of the co-directional coupling.
The magnitude of the spectrum bandwidth Δλ 2 of the envelope of the comb-shaped spectrum in the first and second portions 3 is smaller than the maximum value.

上記実施例のInGaAsP基板における代表的な各値は次
のとおりである: 同方向結合部 長さLcodir 900μm na 3.210 nb 3.307 Λ 16μm 結合係数 17.5cm-1 欠損鋸歯状構造部 長さ 900μm Neff 3.24 L1 75μm L2 7.5μm 基本周期Λsagrat 0.2413μm 結合係数 10cm-1 濾過応答 中心波長 λ=1.550μm 同調範囲 50nm 屈折率変化 0.3nm
Typical values in InGaAsP substrate of the above embodiment are as follows: the same direction coupling unit length L codir 900μm n a 3.210 n b 3.307 Λ 16μm coupling coefficient 17.5cm -1 deficient serrated structure portion length 900 .mu.m N eff 3.24 L 1 75 μm L 2 7.5 μm Fundamental periodΛ sagrat 0.2413 μm Coupling coefficient 10 cm -1 Filtration response Center wavelength λ = 1.550 μm Tuning range 50 nm Refractive index change 0.3 nm

───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 平4−211220(JP,A) 特開 平4−79287(JP,A) 特開 平2−154476(JP,A) 特開 平2−63012(JP,A) 特開 昭63−223605(JP,A) 特開 昭63−26619(JP,A) Applied Physics L etters,Vol.60,No.8 (1992)R.C.Alferness, et.al.「Broadly tun able InGaAsP/InP b uried rib waveguid e vertical coupler filter」pp.980−982 Applied Physics L etters,Vol.60,No.19 (1992)V.Jayaraman,e t.al.「Demonstratio n of broadband tun ability in a semic onductor laser usi ng sampled geating s」pp.2321−2323 ELECTRONICS LETTE RS,Vol.27,No.22(1991) T.Hirata,et.al.「Mo nolithic resonant optical reflector laser diodes」pp.2050 −2051 (58)調査した分野(Int.Cl.7,DB名) G02F 1/025 H01S 3/08 EPAT(QUESTEL)──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-4-211220 (JP, A) JP-A-4-79287 (JP, A) JP-A-2-154476 (JP, A) JP-A-2- 63012 (JP, A) JP-A-63-223605 (JP, A) JP-A-63-26619 (JP, A) Applied Physics Letters, Vol. 60, no. 8 (1992) R.E. C. Alferness, et. al. "Broadly tunable InGaAsP / InP uried rib waveguide vertical coupler filter" pp. 980-982 Applied Physics Letters, Vol. 60, no. 19 (1992) V. Jayaraman, et. al. "Demonstration of broadband tun availability in a semi conductor, laser usinng sampled gratings" pp. 232-1323 ELECTRONICS LETTE RS, Vol. 27, No. 22 (1991) Hirata, et. al. See "Monolytic resonant optical reflector laser diodes" pp. 2050-2051 (58) Field surveyed (Int. Cl. 7 , DB name) G02F 1/025 H01S 3/08 EPAT (QUESTEL)

Claims (4)

(57)【特許請求の範囲】(57) [Claims] 【請求項1】半導体材料基板(1)の第1部分(2)
に、実質的に単一の幅広い透過スペクトル応答ピークを
有する透過形導波構造光フィルタ素子部を形成し、該第
1部分(2)に第1電流注入手段を設けて該第1電流注
入手段から電流を注入することにより、当該透過形導波
構造光フィルタ素子部の幅広いスペクトル応答ピークの
中心波長を偏移可能とした、集積可変波長光フィルタに
おいて、 上記半導体材料基材(1)の第2部分(3)に、複数の
幅狭い反射スペクトル応答ピークを有する反射形導波構
造光フィルタ素子部を形成し、 上記第2部分(3)に第2電流注入手段を設け、該第2
電流注入手段から電流を注入することにより当該反射形
導波構造光フィルタ素子部の各反射スペクトル応答ピー
クの中心波長を僅かに偏移可能とし、 上記第1部分(2)における可変波長透過形導波構造光
フィルタ素子部の透過スペクトル応答ピークの中心波長
に、上記第2部分(3)における可変波長反射形導波構
造光フィルタ素子部の複数の反射スペクトル応答ピーク
のうちの1つの反射スペクトル応答ピークの中心波長を
一致させたとき、該1つの反射スペクトル応答ピークの
みが上記可変波長透過形導波構造光フィルタ素子部の透
過スペクトル応答ピークの波長範囲内に完全に含まれる
ようにして、上記可変波長透過形導波構造光フィルタ素
子部と上記可変波長反射形導波構造光フィルタ素子部と
の合成スペクトル応答が上記1つの反射スペクトル応答
ピークに対応した単一の幅狭い透過スペクトル応答ピー
クを有するようにしたことを特徴とする、集積可変波長
光フィルタ。
1. A first part (2) of a semiconductor material substrate (1).
Forming a transmission type optical filter element having a substantially single broad transmission spectrum response peak, and providing a first current injection means in the first portion (2); In the integrated variable wavelength optical filter, the center wavelength of the broad spectrum response peak of the transmission type waveguide structure optical filter element portion can be shifted by injecting current from the semiconductor material substrate (1). Forming a reflection type waveguide structure optical filter element having a plurality of narrow reflection spectrum response peaks in the second portion (3); providing a second current injection means in the second portion (3);
By injecting current from the current injection means, the center wavelength of each reflection spectrum response peak of the reflection type waveguide structure optical filter element can be slightly shifted, and the variable wavelength transmission type waveguide in the first portion (2) can be used. At the center wavelength of the transmission spectrum response peak of the wave structure optical filter element, one of the plurality of reflection spectrum response peaks of the variable wavelength reflective waveguide structure optical filter element in the second portion (3) is reflected. When the center wavelengths of the peaks are matched, only the one reflection spectrum response peak is completely included within the wavelength range of the transmission spectrum response peak of the variable wavelength transmission type waveguide structure optical filter element section, The combined spectral response of the variable wavelength transmission type waveguide structure optical filter element and the variable wavelength reflection type waveguide structure optical filter element is one of the above. An integrated tunable optical filter having a single narrow transmission spectrum response peak corresponding to a reflection spectrum response peak.
【請求項2】第1部分(2)が、半導体材料基板(1)
上に間隔をあけて配置された第1導波路部(4)及び第
2導波路部(5)、これらの第1導波路部(4)と第2
導波路部(5)間に形成された第1グレーティング構造
部(41)並びに当該第1部分(2)の頂部及び底部にそ
れぞれ配置された第1電極層(6)及び第2電極層
(8)により同方向光結合器を構成する一方、 第2部分(3)が、上記半導体材料基板(1)上に配置
されるとともに上記第1部分(2)における第1導波路
部(4)と連結された導波路部、該導波路部に設けられ
た周期部に欠損した周期的グレーティング構造部(42)
並びに当該第2部分(3)の頂部及び底部にそれぞれ配
置された第2電極層(7)及び背後電極層(8)により
分布型ブラッグ反射器を構成した、請求項1に記載の光
フィルタ。
2. The method according to claim 1, wherein the first part is a semiconductor material substrate.
A first waveguide section (4) and a second waveguide section (5), which are spaced apart from each other, and the first waveguide section (4) and the second
A first grating structure portion (41) formed between the waveguide portions (5) and a first electrode layer (6) and a second electrode layer (8) disposed at the top and bottom of the first portion (2), respectively. ), The second portion (3) is arranged on the semiconductor material substrate (1), and the second portion (3) is formed with the first waveguide portion (4) in the first portion (2). The connected waveguide portion, the periodic grating structure portion missing in the periodic portion provided in the waveguide portion (42)
2. The optical filter according to claim 1, wherein the distributed Bragg reflector is constituted by the second electrode layer (7) and the back electrode layer (8) respectively disposed on the top and the bottom of the second portion (3).
【請求項3】第1グレーティング構造部(41)における
周期的グレーティング構造の周期が10〜50μmとされ
た、請求項2に記載の光フィルタ。
3. The optical filter according to claim 2, wherein the period of the periodic grating structure in the first grating structure (41) is 10 to 50 μm.
【請求項4】第2グレーティング構造部(42)が、第1
グレーティング構造部(41)の周期的グレーティング構
造よりも短い周期をもって繰返す周期的グレーティング
構造領域(43)を含む、請求項2又は請求項3に記載の
光フィルタ。
4. The first grating structure (42) is provided with a first grating structure (42).
4. The optical filter according to claim 2, further comprising a periodic grating structure region (43) that repeats with a shorter period than the periodic grating structure of the grating structure (41). 5.
JP50761594A 1992-09-24 1993-09-17 Integrated tunable optical filter Expired - Fee Related JP3185930B2 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
BE9200838A BE1006207A3 (en) 1992-09-24 1992-09-24 INTEGRATED tunable optical FILTER.
BE9200838 1992-09-24
PCT/BE1993/000061 WO1994007178A1 (en) 1992-09-24 1993-09-17 Integrated tunable optical filter

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JPH07501628A JPH07501628A (en) 1995-02-16
JP3185930B2 true JP3185930B2 (en) 2001-07-11

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EP (1) EP0613571B1 (en)
JP (1) JP3185930B2 (en)
AT (1) ATE169127T1 (en)
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WO (1) WO1994007178A1 (en)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE0100611L (en) 2001-02-22 2002-08-23 Altitun Ab A method of loss compensating a tunable filter for a laser, as well as such a filter
SE518476C2 (en) 2001-02-22 2002-10-15 Altitun Ab Method for improving the selectivity of a tunable waveguide filter
US6674929B2 (en) * 2001-06-01 2004-01-06 Lightcross, Inc. Tunable optical filter
US7653093B2 (en) * 2001-09-10 2010-01-26 Imec Widely tunable twin guide laser structure
US7023886B2 (en) 2001-11-08 2006-04-04 Intel Corporation Wavelength tunable optical components
US6810168B1 (en) 2002-05-30 2004-10-26 Kotura, Inc. Tunable add/drop node

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS60260024A (en) * 1984-06-07 1985-12-23 Kokusai Denshin Denwa Co Ltd <Kdd> Optical modulating element
JP2659199B2 (en) * 1987-11-11 1997-09-30 日本電気株式会社 Tunable wavelength filter
US5147825A (en) * 1988-08-26 1992-09-15 Bell Telephone Laboratories, Inc. Photonic-integrated-circuit fabrication process
US5220573A (en) * 1989-03-10 1993-06-15 Canon Kabushiki Kaisha Optical apparatus using wavelength selective photocoupler
JP2957240B2 (en) * 1990-07-20 1999-10-04 キヤノン株式会社 Tunable semiconductor laser
JPH04138427A (en) * 1990-09-28 1992-05-12 Oki Electric Ind Co Ltd Optical wavelength filter device
US5253314A (en) * 1992-01-31 1993-10-12 At&T Bell Laboratories Tunable optical waveguide coupler
US5325392A (en) * 1992-03-06 1994-06-28 Nippon Telegraph And Telephone Corporation Distributed reflector and wavelength-tunable semiconductor laser
SE470454B (en) * 1992-08-26 1994-04-11 Ericsson Telefon Ab L M Optical filter device

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
Applied Physics Letters,Vol.60,No.19(1992)V.Jayaraman,et.al.「Demonstration of broadband tunability in a semiconductor laser using sampled geatings」pp.2321−2323
Applied Physics Letters,Vol.60,No.8(1992)R.C.Alferness,et.al.「Broadly tunable InGaAsP/InP buried rib waveguide vertical coupler filter」pp.980−982
ELECTRONICS LETTERS,Vol.27,No.22(1991)T.Hirata,et.al.「Monolithic resonant optical reflector laser diodes」pp.2050−2051

Also Published As

Publication number Publication date
DE69320022D1 (en) 1998-09-03
JPH07501628A (en) 1995-02-16
DE69320022T2 (en) 1999-03-25
ATE169127T1 (en) 1998-08-15
BE1006207A3 (en) 1994-06-07
USRE36710E (en) 2000-05-23
EP0613571B1 (en) 1998-07-29
EP0613571A1 (en) 1994-09-07
WO1994007178A1 (en) 1994-03-31

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